The invention relates to a multiple-coordinate scanner with regulated scanning force for scanning objects. With this scanner, the precise location of the scanned point on the object can be ascertained. The scanner is preferably used in multi-dimensional length-measuring apparatus. The multiple-coordinate scanner can be used in combination with a measuring machine for scanning and measuring arbitrarily curved three-dimensional surfaces such as are used in gear manufacturing.
Multiple-coordinate scanners are known (German Pat. No. 22 42 355), the structure of which comprises a torsionally rigid succession of straight-line guides, each of which is associated with a travel measuring system. The measuring force is generated via plunger coils, or dynamic coils, independently of the force actually occurring, and is therefore subject to certain fluctuations. The accuracy of the measurement is affected by these fluctuations, as by the different flexions of the measuring system. The degree of possible deflection of the measuring scanner is thus severely restricted. Because of its necessarily rigid embodiment the measuring machine has large masses that must be moved, the restricted deflectability also severely restricts the speed of deflection, which results in measuring times of considerable length.
The location of the scanning point of the scanning ball on the object is indirectly determined from the magnitude of the deflection of the individual straight-line guides.